<ARTICLE> UT
<LEGEND>
This schedule contains summary financial information extracted from the
balance sheet, statement of income and statement of cash flows contained in
Form 10-Q of Commonwealth Energy System for the six months ended September 30,
1995 and is qualified in its entirety by reference to such financial
statements.
</LEGEND>
<CIK> 0000071304
<NAME> COMMONWEALTH ENERGY SYSTEM
<MULTIPLIER> 1,000
       
                                
<FISCAL-YEAR-END>                  DEC-31-1995
<PERIOD-END>                       SEP-30-1995
<PERIOD-TYPE>                            9-MOS
<BOOK-VALUE>                          PER-BOOK
<TOTAL-NET-UTILITY-PLANT>            1,015,634
<OTHER-PROPERTY-AND-INVEST>             13,722
<TOTAL-CURRENT-ASSETS>                 135,929
<TOTAL-DEFERRED-CHARGES>               153,755
<OTHER-ASSETS>                          15,356
<TOTAL-ASSETS>                       1,334,396
<COMMON>                                42,836
<CAPITAL-SURPLUS-PAID-IN>              109,632
<RETAINED-EARNINGS>                    227,404
<TOTAL-COMMON-STOCKHOLDERS-EQ>         379,872
<PREFERRED-MANDATORY>                   13,840
<PREFERRED>                                  0
<LONG-TERM-DEBT-NET>                   396,551
<SHORT-TERM-NOTES>                      22,675
<LONG-TERM-NOTES-PAYABLE>                    0
<COMMERCIAL-PAPER-OBLIGATIONS>               0
<LONG-TERM-DEBT-CURRENT-PORT>           40,973
<PREFERRED-STOCK-CURRENT>                  820
<CAPITAL-LEASE-OBLIGATIONS>             13,737
<LEASES-CURRENT>                         1,619
<OTHER-ITEMS-CAPITAL-AND-LIAB>         464,309
<TOT-CAPITALIZATION-AND-LIAB>        1,334,396
<GROSS-OPERATING-REVENUE>              680,244
<INCOME-TAX-EXPENSE>                    12,772
<OTHER-OPERATING-EXPENSES>             601,836
<TOTAL-OPERATING-EXPENSES>             614,608
<OPERATING-INCOME-LOSS>                 65,636
<OTHER-INCOME-NET>                       1,960
<INCOME-BEFORE-INTEREST-EXPEN>          67,596
<TOTAL-INTEREST-EXPENSE>                33,117
<NET-INCOME>                            34,479
<PREFERRED-STOCK-DIVIDENDS>                843
<EARNINGS-AVAILABLE-FOR-COMM>           33,636
<COMMON-STOCK-DIVIDENDS>                23,958
<TOTAL-INTEREST-ON-BONDS>               29,098
<CASH-FLOW-OPERATIONS>                 105,230
<EPS-PRIMARY>                             3.17
<EPS-DILUTED>                                0